This patch makes 3 changes:
- It makes upas/fs send plumb messages when a message
changes in the background (eg, someone on another imap
connection opens a message and sets the read flag)
- It makes faces not complain when it gets one of these
new modify messages.
- It makes acme/Mail update the flags in the display
when it gets one of these messages.
on systems with serial console and graphics such as the raspberry pi,
it is nice to get a system shell on the serial console even when no
monitor is connected.
the console command runs a command or the system shell under
a new instance of kbdfs, optionally providing a serial console
when $console environment variable is set.
comparing m with MACHP() is wrong as m is a constant on 386.
add procflushothers(), which flushes all processes except up
using common procflushmmu() routine.
procflushmmu() returns once all *OTHER* processors that had
matching processes running on them flushed ther tlb/mmu state.
the caller of procflush...() takes care of flushing "up" by
calling flushmmu() later.
if the current process matched, then that means m->flushmmu
would be set, and hzclock() would call flushmmu() again.
to avoid this, we now check up->newtlb in addition to m->flushmmu
in hzclock() before calling flushmmu().
we also maintain information on which process on what processor
to wait for locally, which helps making progress when multiple
procflushmmu()'s are running concurrently.
in addition, this makes the wait condition for procflushmmu()
more sophisticated, by validating if the processor still runs
the selected process and only if it matchatches, considers
the MACHP(nm)->flushmmu flag.
The code had a nested use of the follow() function that could cause +=+
and -=- to register as ++ and --. The first follow() to execute could
consume a character and match and then the second follow() could consume
another character and match. For example i-=-10 would result in a syntax
error and i-=- would decrement i.
(imported from plan9port commit f1dd3f065a97f57bf59db2e3284868e181734159)
the change to support no-execute bits broke the original
raspberry pi1, as it uses backwards compatible page table
format.
to use the XN bit, subpage AP bits have to be disabled
using the XP bit in CP15 Control Register c1 Bit 23.
When plumbing an address like `3-`, Acme selects line 1,
and similarly `3+` selects line 5.
The same problem can be observed for character addresses (`#123+`)
but _not_ for ones like `+`, `.+` or `/foo/+`:
The problem only occurs when a number is followed by a direction (`-`/`+`).
Following along with the example `3-` through `address` (in addr.c):
We read `3` into `c` and match the `case` on line 239.
The `while` loop on line 242ff reads additional digits into `c`
and puts the first non-digit back by decrementing the index `q`.
Then we find the range for line 3 on line 251 and continue.
On the next iteration, we set `prevc` to the last `c`,
but since that part read ahead _into `c`_,
`c` is currently the _next_ character we will read, `-`,
and now `prevc` is too.
Then in the case block (line 210) the condition on line 211 holds
and Acme believes that it has read two `-` in sequence
and modifies the range to account for the “first” `-`.
The “second” `-` gets applied after the loop is done, on line 292.
So the general problem is:
While reading numbers, Acme reads the next character after the number into `c`.
It decrements the counter to ensure it will read it again on the next iteration,
but it still uses it to update `prevc`.
This change solves the problem by reading digits into `nc` instead.
This variable is used to similar effect in the block for directions (line 212)
and fills the role of “local `c` that we can safely use to read ahead” nicely.
(imported from plan9front a82a8b6368274d77d42f526e379b74e79c137e26)
To reproduce, create a column with at least two windows and resize
acme to have almost zero height.
(imported from plan9port commit 76b9347a5fa3a0970527c6ee1b97ef1c714f636b)
when a process does an exec syscall, procsetup() is called and
we have to disable the debug watchpoint registers. just clearing
p->dr is not enougth as we are not going thru a procsave() and
procrestore() cycle which would disable and reload the saved
debug registers.
instead of clearing debug registers in procfork(), we should
clear the saved debug registers before a process goes to die
(pexit() calls sched() with up->state = Moribund) as the Proc
structure can get reused for kernel processes (kproc) which
never call procfork() and would therefore have debug registers
loaded.
do incremental imap fetches after startup, fixes validity handling,
record flags correctly when we aren't in the process of directly
updating a message, fixes off by one in flag parsing, fixes
mis-indexing messages in sync when we get an unsolicited fetch
response.
for better system diagnostics, we *ALWAYS* want to record the parent
pid of a user process, regardless of if the child will post a wait
record on exit or not.
for that, we reverse the roles of Proc.parent and Proc.parentpid so
Proc.parentpid will always be set on rfork() and the Proc.parent
pointer will point to the parent's Proc structure or is set to nil
when no wait record should be posted on exit (RFNOWAIT flag).
this means that we can get the pid of the original parent process
from /proc, regardless of the the child having rforked with the
RFNOWAIT flag. this improves the output of pstree(1) somewhat if
the parent is still alive. note that theres no guarantee that the
parent pid is still valid.
the conditions are unchanged:
a user process that will post wait record has:
up->kp == 0 && up->parent != nil && up->parent->pid == up->parentpid
the boot process is:
up->kp == 0 && up->parent == nil && up->parentpid == 0
and kproc's have:
up->kp != 0 && up->parent == nil && up->parentpid == 0
this is a reimplementation of infernos os(1) command, which
allows running commands in the underhying host operating
system when inferno runs in hosted mode (emu). but unlike
inferno, we want to use it to run commands on the client
side of a inferno or drawterm session from the plan9 cpu
server, so it defaults to /mnt/term/cmd for the mountpoint.
Previously, reads of wctl files would return one byte less than
requested as the returned string must be null terminated. Now we pass
the actual size of the allocated buffer to the handler, which is large
enough to accommodate a trailing partial rune and terminating null
byte.
Ori_B reports that his controller gets stuck in the ahciencreset()
wait loop. so we implement a 1000 ms timeout. we replace delay()
with esleep() as we are always called from the ledkproc().
blink() could enter infinite delay loop as well, so instead of
waiting for the message to get transmitted we exit making it
non-blocking (we will get called again anyway).
the access to the controller map[] was wrong in ledkproc(). the
index is the controller number, not the drive number!
Support for 'path=', 'uname=', 'gname=', 'size=', and 'atime=' pax
headers is useful. Others are ignored, possibly with a warning.
We were running into missing support with the 'go' extraction.
At the same time, this cleans up the way that we handle paths,
getting rid of static buffers with hidden space at the front.
when making outgoing connections, the source ip was selected
by just iterating from the first to the last interface and
trying each local address until a route was found. the result
was kind of hard to predict as it depends on the interface
order.
this change replaces the algorithm with the route lookup algorithm
that we already have which takes more specific desination and
source prefixes into account. so the order of interfaces does
not matter anymore.
Tar specifies that a filename ending with '/' is a directory. We were
incorrectly looking at the short name. This meant that when we have long
filenames with a '/' at the 100th character, we would decide it was a
directory.
This change uses the long name when deciding the size for extraction,
and trusts the header size when just skipping forward in the stream.
extract1() expects two extra bytes to be avilabe before
fname buffer so it can prepend ./ before the name. this
used to be the case with name(), but was violated when
long name support was added and getname() was used in
place of name() which did not reserve the 2 extra bytes.
this change reserves two extra bytes in the getname()'s
static buffer and also removes the extra copy as name()
already makes a copy.
Since numeric timezone offsets are relative to GMT, initialise zone to
GMT so tm2sec(2) does not assume local time.
Note that if strtotm encounters a timezone *string* and consequently
overwrites zone then we will end up in the same mess since tm2sec(2)
only deals with GMT or local time.
there was a race between the sendproc putting the request on
the sreqrd[] id and the recvproc handling the response, and
potentially freeing the request before the sendproc() was
finished with the request (or the fid).
so we defer allocating a request id and putting it on the
sreqrd[] stage after we have completely generated the
request in vpack(). this prevents the handling of the request
before it is even sent.
this also means that the SReq should not be touched after
calling sendpkt(), submitreq(), submitsreq().
secondly, putsfid() needs to acquire the RWLock to make sure
sendproc() is finished with the request. the scenario is that
recvproc() can call respond() on the request before sendproc()
has unlocked the SFid.
move digest pointer into Mtree structrue and embed it into Idx struct
(which is embedded in Message) to avoid one level of indirection
during mtreecmp().
get rid of mtreeisdup(). instead we have mtreeadd() return the old
message in case of a collision. this avoids double lookup.
increase the hash table size for henter() and make it a prime.
on 386, the kernel memory region is mapped using huge 4MB pages
(when supported by the cpu). so the uncached pte manipulation
does not work to map the cursor data with uncached attribute.
instead, we allocate a memory page using newpage() and map
it globally using vmap(), which maps it uncached.
after issuing CR_RESETEP command, we have to invalidate
the endpoints output context buffer so that the halted/error
status reflects the new state. not doing so resulted in
the halted state to be stuck and we continued issuing
endpoint reset commands when we where already recovered.
handle the devusb Ep.clrhalt flag from devusb that userspace
uses to force a endpoint reset on the next transaction.
for servers that handle incoming network connections and authentication,
change the owner of the network connection file to the authenticated user
after successfull authentication.
note that we set the permissions as well to 0660 because old devip used
to unconditionally set the bits.
permission checking had the "other" and "owner" bits swapped plus incoming
connections where always owned by "network" instead of the owner of
the listening connection. also, ipwstat() was not effective as the uid
strings where not parsed.
this fixes the permission checks for data/ctl/err file and makes incoming
connections inherit the owner from the listening connection.
we also allow ipwstat() to change ownership to the commonuser() or anyone
if we are eve.
we might have to add additional restrictions for none at a later point...
we want devip to get reattached after hostowner has been written. factotum
already handles this with a private authdial() routine that mounts devip
when it is not present. so we detach devmnt before starting factotum,
and attach once factotum finishes.
the locking in proctext() is wrong. we have to acquire Proc.seglock
when reading segments from Proc.seg[] as segments do not
have a private freelist and can therefore be reused for other
data structures.
once we have Proc.seglock acquired, check that the process pid
is still valid so we wont accidentally read some other processes
segments. (for both proctext() and procctlmemio()). this also
should give better error message to distinguish the case when
the process did segdetach() the segment in question before we
could acquire Proc.seglock.
declare private functions as static.
there was a small window between modifying mmutop and switching the
asid where the core could bring in the new entries under the old asid
into the tlb due to speculation / prefetching.
this change moves the entering of the page tables into mmutop after
setttbr() to prevent this scenario.
due to us switching to the resereved asid 0 on procsave()->putasid(),
the only asid that could have potentially been poisoned would be asid 0
which does not have any user mappings. so this did not show any noticable
effect.
when a process state has not been saved (Proc.mach != nil)
then the contents of Proc.sched should be considered invalid.
to approximate a stacktrace in this case, we use the error
stack and get a stacktrace from the last waserror() call.
pexit() and pprint() can get called outside of a syscall
(from procctl()) with a process that is in active note
handling and require floating point in the kernel on amd64
for aesni (devtls).
This fixes ocaml on non-x86 architectures, where we have code
that looks like:
#define Fl_head ((uintptr_t)(&sentinel.first_field))
Without this change, we get an error about a non-constant
initializer. This change takes the checks for pointers and
makes them apply to all expressions. It also makes the checks
stricter, preventing the following from compiling to junk:
int x;
int y = 42;
int *p = &x + y
the following code reproduces the crash:
void
foo(void)
{
}
void
main(int argc, char **argv)
{
(void)(1 ? (void)0 : foo());
}
the problem is that side() gives a false positive on the OCOND
with later constant folding eleminating the acutal side effect
and OCAST ending up with two nested OCATS with the nested one
being zapped (type == T).
make exec() clear the per process error string
to avoid spurious errors and confusion.
the errstr() syscall used to always swap the
maximum buffer size with memmove(), which is
problematic as this gives access to the garbage
beyond the NUL byte. worse, newproc(), werrstr()
and rerrstr() only clear the first byte of the
input buffer. so random stack rubble could be
leaked across processes.
we change the errstr() syscall to not copy
beyond the NUL byte.
the manpage also documents that errstr() should
truncate on a utf8 boundary so we use utfecpy()
to ensure proper NUL termination.
kvik writes:
dnsquery(8) prints the interactive prompt on stdout together with
query results, making scripted usage unnecessarily difficult.
A straightforward solution is prompting on stderr instead: as
practiced by rc(1), among many others -- promptly taking care of
the issue:
; echo 9front.org mx | ndb/dnsquery >[2]/dev/null
kvik writes:
I needed to convert the RSA private key that was laying around in
secstore into a format understood by UNIX® tools like SSH.
With asn12rsa(8) we can go from the ASN.1/DER to Plan 9 format, but not
back - so I wrote the libsec function asn1encodeRSApriv(2) and used it in
rsa2asn1(8) by adding the -a flag which causes the full private key to be
encoded and output.
the idea is to catch bugs and make kernel exploitation
harder by mapping the kernel text section readonly
and everything else no-execute.
l.s maps the KZERO address space using 2MB pages so
to get the 4K granularity for the text section we use
the new ptesplit() function to split that mapping up.
we need to set EFER no-execute enable bit early
in apbootstrap so secondary application processors
will understand the NX bit in our shared kernel page
tables. also APBOOTSTRAP needs to be kept executable.
rebootjump() needs to mark REBOOTADDR page executable.
mischief reports:
this assembler input assembles with 6a but makes 6l crash.
// 6a l.s
// 6l l.6
// _intrr: unknown relation: TEXT in _intrr
// 6l 511: suicide: sys: trap: fault write addr=0x18 pc=0x20789c
TEXT noteret(SB), 1, $-4
CLI
JMP _intrestore // works when commented
TEXT _intrr(SB), 1, $-4
_intrestore:
RET
TEXT _main(SB), 1, $-4
RET
the user should not be able to change the cache
attributes for a segment in segattach() as this
can cause the same memory to be mapped with
conflicting attributes in the cache.
SG_TEXT should always be mapped with SG_RONLY
attribute. so fix data2txt() to follow the rules.
fault() now has an additional pc argument that is
used to detect fault on a non-executable segment.
that is, we check on read fault if the segment
has the SG_NOEXEC attribute and the program counter
is within faulting page.
a portable SG_NOEXEC segment attribute was added to allow
non-executable (physical) segments. which will set the
PTENOEXEC bits for putmmu().
in the future, this can be used to make non-executable
stack / bss segments.
the SG_DEVICE attribute was added to distinguish between
mmio regions and uncached memory. only matterns on arm64.
on arm, theres the issue that PTEUNCACHED would have
no bits set when using the hardware bit definitions.
this is the reason bcm, kw, teg2 and omap kernels use
arteficial PTE constants. on zynq, the XN bit was used
as a hack to give PTEUNCACHED a non-zero value and when
the bit is clear then cache attributes where added to
the pte.
to fix this, PTECACHED constant was added.
the portable mmu code in fault.c will now explicitely set
PTECACHED bits for cached memory and PTEUNCACHED for
uncached memory. that way the hardware bit definitions
can be used everywhere.
on the 2GB and 4GB raspberry pi 4 variants, there are two
memory regions for ram:
[0x00000000..0x3e600000)
[0x40000000..0xfc000000)
the framebuffer is somewhere at the end of the first
GB of memory.
to handle these, we append the region base and limit
of the second region to *maxmem= like:
*maxmem=0x3e600000 0x40000000 0xfc000000
the mmu code has been changed to have non-existing
ram unmapped and mmukmap() now uses small 64K pages
instead of 512GB pages to avoid aliasing (framebuffer).
the VIRTPCI mapping has been removed as we now have
a proper vmap() implementation which assigns vritual
addresses automatically.
this adds a 4GB KMAP window into the kernel address space
so we can access all physical ram on raspberry pi 4 for
user pages.
note that kernel memory above KZERO is still limited
to 1GB because of DMA restrictions.
according to the following linux change, BCM2711 uses a different
method for changing pullup/down mode:
abcfd09286 (diff-cf078559c38543ac72c5db99323e236d)
gpiomeminit() was broken, using virtual address for the gpio physseg
instead of the physical one.
cleanup the code, avoid repetition by declaring static u32int *regs
variable. make local variable names consistent.
the raspberry pi 4 has a new interrupt controller and
pci support, so get rid of intrenable() macro and
properly make intrenable function with tbdf argument.
the raspberry pi4 firmware refuses to enable the GIC interrup controller
for arm64 when the .img file is not a multiple of 4 bytes. yes, this
is insane and nowhere documented.
the new raspberry pi 4 firmware for arm64 seems to have
broken atag support. so we now parse the device tree
structure to get the bootargs and memory configuration.
Ori Bernstein had Sunrise Point-H USB 3.0 xHCI Controller that would mysteriously
crash on the 5th ENABLESLOT command. This was reproducable by even just allocating
slots in a loop right after init.
It turns out, the 1.2 spec extended the Max Scratchpad Buffers in HCSPARAMS2 so our
driver would not allocate enougth scratchpad buffers and controller firmware would
crash once it went beyond our allocated scratchpad buffer array.
This change also fixes:
- ignore bits 16:31 in PAGESIZE register
- preserve bits 10:31 in the CONFIG register
- handle ADDESSDEV command failure (so it can be retried)
preallocate 2% of user pages for page tables and MMU structures
and keep them mapped in the VMAP range. this leaves more space
in the KZERO window and avoids running out of kernel memory on
machines with large amounts of memory.
when a operation receives a chain of OINDEX nodes as its operands,
each indexing step used to allocate a new index register. this
is wastefull an can result in running out of fixed registers on 386
for code such as: x = a[a[a[a[i]]]].
instead we attempt to reuse the destination register of the operation
as the index register if it is not otherwise referenced. this results
in the index chain to use a single register for index and result and
leaves registers free to be used for something usefull instead.
for 6c, try to avoid R13 as well as BP index base register.
